13215728 has 10 divisors (see below), whose sum is σ = 25605504. Its totient is φ = 6607856.

The previous prime is 13215721. The next prime is 13215739. The reversal of 13215728 is 82751231.

It is a self number, because there is not a number n which added to its sum of digits gives 13215728.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (13215721) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 412976 + ... + 413007.

Almost surely, 2^13215728 is an apocalyptic number.

It is an amenable number.

13215728 is a deficient number, since it is larger than the sum of its proper divisors (12389776).

13215728 is an equidigital number, since it uses as much as digits as its factorization.

13215728 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 825991 (or 825985 counting only the distinct ones).

The product of its digits is 3360, while the sum is 29.

The square root of 13215728 is about 3635.3442753060. The cubic root of 13215728 is about 236.4269776807.

Adding to 13215728 its reverse (82751231), we get a palindrome (95966959).

The spelling of 13215728 in words is "thirteen million, two hundred fifteen thousand, seven hundred twenty-eight".